83 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			83 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * Copyright (c) 2003, 2007-14 Matteo Frigo | ||
|  |  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology | ||
|  |  * | ||
|  |  * This program is free software; you can redistribute it and/or modify | ||
|  |  * it under the terms of the GNU General Public License as published by | ||
|  |  * the Free Software Foundation; either version 2 of the License, or | ||
|  |  * (at your option) any later version. | ||
|  |  * | ||
|  |  * This program is distributed in the hope that it will be useful, | ||
|  |  * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
|  |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | ||
|  |  * GNU General Public License for more details. | ||
|  |  * | ||
|  |  * You should have received a copy of the GNU General Public License | ||
|  |  * along with this program; if not, write to the Free Software | ||
|  |  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA | ||
|  |  * | ||
|  |  */ | ||
|  | 
 | ||
|  | #include "kernel/ifftw.h"
 | ||
|  | 
 | ||
|  | 
 | ||
|  | /* Given a solver which_dim, a vector sz, and whether or not the
 | ||
|  |    transform is out-of-place, return the actual dimension index that | ||
|  |    it corresponds to.  The basic idea here is that we return the | ||
|  |    which_dim'th valid dimension, starting from the end if | ||
|  |    which_dim < 0. */ | ||
|  | static int really_pickdim(int which_dim, const tensor *sz, int oop, int *dp) | ||
|  | { | ||
|  |      int i; | ||
|  |      int count_ok = 0; | ||
|  |      if (which_dim > 0) { | ||
|  |           for (i = 0; i < sz->rnk; ++i) { | ||
|  |                if (oop || sz->dims[i].is == sz->dims[i].os) | ||
|  |                     if (++count_ok == which_dim) { | ||
|  |                          *dp = i; | ||
|  |                          return 1; | ||
|  |                     } | ||
|  |           } | ||
|  |      } | ||
|  |      else if (which_dim < 0) { | ||
|  |           for (i = sz->rnk - 1; i >= 0; --i) { | ||
|  |                if (oop || sz->dims[i].is == sz->dims[i].os) | ||
|  |                     if (++count_ok == -which_dim) { | ||
|  |                          *dp = i; | ||
|  |                          return 1; | ||
|  |                     } | ||
|  |           } | ||
|  |      } | ||
|  |      else { /* zero: pick the middle, if valid */ | ||
|  | 	  i = (sz->rnk - 1) / 2; | ||
|  | 	  if (i >= 0 && (oop || sz->dims[i].is == sz->dims[i].os)) { | ||
|  | 	       *dp = i; | ||
|  | 	       return 1; | ||
|  | 	  } | ||
|  |      } | ||
|  |      return 0; | ||
|  | } | ||
|  | 
 | ||
|  | /* Like really_pickdim, but only returns 1 if no previous "buddy"
 | ||
|  |    which_dim in the buddies list would give the same dim. */ | ||
|  | int X(pickdim)(int which_dim, const int *buddies, size_t nbuddies, | ||
|  | 	       const tensor *sz, int oop, int *dp) | ||
|  | { | ||
|  |      size_t i; | ||
|  |      int d1; | ||
|  | 
 | ||
|  |      if (!really_pickdim(which_dim, sz, oop, dp)) | ||
|  |           return 0; | ||
|  | 
 | ||
|  |      /* check whether some buddy solver would produce the same dim.
 | ||
|  |         If so, consider this solver unapplicable and let the buddy | ||
|  |         take care of it.  The smallest-indexed buddy is applicable. */ | ||
|  |      for (i = 0; i < nbuddies; ++i) { | ||
|  |           if (buddies[i] == which_dim) | ||
|  |                break;  /* found self */ | ||
|  |           if (really_pickdim(buddies[i], sz, oop, &d1) && *dp == d1) | ||
|  |                return 0; /* found equivalent buddy */ | ||
|  |      } | ||
|  |      return 1; | ||
|  | } |